/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/****************************************************************************
 * apps/include/netutils/base64.h
 *
 * This file is part of the NuttX RTOS:
 *
 *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
 *   Author: Darcy Gong
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <apps/netutils/urldecode.h>

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE
#define IS_HEX_CHAR(ch) \
	((ch >= '0' && ch <= '9') || \
	(ch >= 'a' && ch <= 'f') || \
	(ch >= 'A' && ch <= 'F'))

#define HEX_VALUE(ch, value) \
	if (ch >= '0' && ch <= '9') { \
		value = ch - '0'; \
	} \
	else if (ch >= 'a' && ch <= 'f') { \
		value = ch - 'a' + 10; \
	} else { \
		value = ch - 'A' + 10; \
	}
#endif

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: from_hex
 *
 * Description:
 *   Converts a hex character to its integer value,
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE_NEWMEMORY
static char from_hex(char ch)
{
	return isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10;
}
#endif

/****************************************************************************
 * Name:
 *
 * Description:
 *   Converts an integer value to its hex character,
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE_NEWMEMORY
static char to_hex(char code)
{
	static const char hex[] = "0123456789abcdef";
	return hex[code & 15];
}
#endif

/****************************************************************************
 * Name: int2h
 *
 * Description:
 *   Convert a single character to a 2 digit hex str a terminating '\0' is
 *   added
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_AVR_URLCODE
static void int2h(char c, char *hstr)
{
	hstr[1] = (c & 0xf) + '0';
	if ((c & 0xf) > 9) {
		hstr[1] = (c & 0xf) - 10 + 'a';
	}

	c = (c >> 4) & 0xf;
	hstr[0] = c + '0';
	if (c > 9) {
		hstr[0] = c - 10 + 'a';
	}

	hstr[2] = '\0';
}
#endif

/****************************************************************************
 * Name: h2int
 *
 * Description:
 *   Convert a single hex digit character to its integer value.
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_AVR_URLCODE
static unsigned char h2int(char c)
{
	if (c >= '0' && c <= '9') {
		return ((unsigned char)c - '0');
	}

	if (c >= 'a' && c <= 'f') {
		return ((unsigned char)c - 'a' + 10);
	}

	if (c >= 'A' && c <= 'F') {
		return ((unsigned char)c - 'A' + 10);
	}

	return 0;
}
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name:
 *
 * Description:
 *   Returns a url-encoded version of str.
 *
 *   IMPORTANT: be sure to free() the returned string after use.
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE_NEWMEMORY
char *url_encode(char *str)
{
	char *pstr = str;
	char *buf = malloc(strlen(str) * 3 + 1);
	char *pbuf = buf;

	while (*pstr) {
		if (isalnum(*pstr) || *pstr == '-' || *pstr == '_' || *pstr == '.' || *pstr == '~') {
			*pbuf++ = *pstr;
		} else if (*pstr == ' ') {
			*pbuf++ = '+';
		} else {
			*pbuf++ = '%';
			*pbuf++ = to_hex(*pstr >> 4);
			*pbuf++ = to_hex(*pstr & 15);
		}

		pstr++;
	}

	*pbuf = '\0';
	return buf;
}
#endif

/****************************************************************************
 * Name: url_decode
 *
 * Description:
 *   Returns a url-decoded version of str.
 *
 *   IMPORTANT: be sure to free() the returned string after use.
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE_NEWMEMORY
char *url_decode(char *str)
{
	char *pstr = str;
	char *buf = malloc(strlen(str) + 1);
	char *pbuf = buf;

	while (*pstr) {
		if (*pstr == '%') {
			if (pstr[1] && pstr[2]) {
				*pbuf++ = from_hex(pstr[1]) << 4 | from_hex(pstr[2]);
				pstr += 2;
			}
		} else if (*pstr == '+') {
			*pbuf++ = ' ';
		} else {
			*pbuf++ = *pstr;
		}

		pstr++;
	}

	*pbuf = '\0';
	return buf;
}
#endif

/****************************************************************************
 * Name: urlencode
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE
char *urlencode(const char *src, const int src_len, char *dest, int *dest_len)
{
	static const unsigned char hex_chars[] = "0123456789ABCDEF";
	const unsigned char *pSrc;
	const unsigned char *pEnd;
	char *pDest;

	pDest = dest;
	pEnd = (unsigned char *)src + src_len;
	for (pSrc = (unsigned char *)src; pSrc < pEnd; pSrc++) {
		if ((*pSrc >= '0' && *pSrc <= '9') || (*pSrc >= 'a' && *pSrc <= 'z') || (*pSrc >= 'A' && *pSrc <= 'Z') || (*pSrc == '_' || *pSrc == '-' || *pSrc == '.' || *pSrc == '~')) {
			*pDest++ = *pSrc;
		} else if (*pSrc == ' ') {
			*pDest++ = '+';
		} else {
			*pDest++ = '%';
			*pDest++ = hex_chars[(*pSrc) >> 4];
			*pDest++ = hex_chars[(*pSrc) & 0x0F];
		}
	}

	*pDest = '\0';
	*dest_len = pDest - dest;
	return dest;
}
#endif

/****************************************************************************
 * Name: urldecode
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE
char *urldecode(const char *src, const int src_len, char *dest, int *dest_len)
{
	const unsigned char *pSrc;
	const unsigned char *pEnd;
	char *pDest;
	unsigned char cHigh;
	unsigned char cLow;
	int valHigh;
	int valLow;

	pDest = dest;
	pSrc = (unsigned char *)src;
	pEnd = (unsigned char *)src + src_len;
	while (pSrc < pEnd) {
		if (*pSrc == '%' && pSrc + 2 < pEnd) {
			cHigh = *(pSrc + 1);
			cLow = *(pSrc + 2);

			if (IS_HEX_CHAR(cHigh) && IS_HEX_CHAR(cLow)) {
				HEX_VALUE(cHigh, valHigh)
				HEX_VALUE(cLow, valLow)
				* pDest++ = (valHigh << 4) | valLow;
				pSrc += 3;
			} else {
				*pDest++ = *pSrc;
				pSrc++;
			}
		} else if (*pSrc == '+') {
			*pDest++ = ' ';
			pSrc++;
		} else {
			*pDest++ = *pSrc;
			pSrc++;
		}
	}

	*pDest = '\0';
	*dest_len = pDest - dest;
	return dest;
}
#endif

/****************************************************************************
 * Name: urlencode_len
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE
int urlencode_len(const char *src, const int src_len)
{
	const unsigned char *pSrc;
	const unsigned char *pEnd;
	int len = 0;

	pEnd = (unsigned char *)src + src_len;
	for (pSrc = (unsigned char *)src; pSrc < pEnd; pSrc++) {
		if ((*pSrc >= '0' && *pSrc <= '9') || (*pSrc >= 'a' && *pSrc <= 'z') || (*pSrc >= 'A' && *pSrc <= 'Z') || (*pSrc == '_' || *pSrc == '-' || *pSrc == '.' || *pSrc == '~' || *pSrc == ' ')) {
			len++;
		} else {
			len += 3;
		}
	}

	return len;
}
#endif

/****************************************************************************
 * Name: urldecode_len
 ****************************************************************************/

#ifdef CONFIG_CODECS_URLCODE
int urldecode_len(const char *src, const int src_len)
{
	const unsigned char *pSrc;
	const unsigned char *pEnd;
	int len = 0;
	unsigned char cHigh;
	unsigned char cLow;

	pSrc = (unsigned char *)src;
	pEnd = (unsigned char *)src + src_len;
	while (pSrc < pEnd) {
		if (*pSrc == '%' && pSrc + 2 < pEnd) {
			cHigh = *(pSrc + 1);
			cLow = *(pSrc + 2);

			if (IS_HEX_CHAR(cHigh) && IS_HEX_CHAR(cLow)) {
				pSrc += 2;
			}
		}

		len++;
		pSrc++;
	}

	return len;
}
#endif

/****************************************************************************
 * Name: urlrawdecode
 *
 * Description:
 * decode a url string e.g "hello%20joe" or "hello+joe" becomes "hello joe"
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_AVR_URLCODE
void urlrawdecode(char *urlbuf)
{
	char c;
	char *dst;
	dst = urlbuf;
	while ((c = *urlbuf)) {
		if (c == '+') {
			c = ' ';
		}

		if (c == '%') {
			urlbuf++;
			c = *urlbuf;
			urlbuf++;
			c = (h2int(c) << 4) | h2int(*urlbuf);
		}

		*dst = c;
		dst++;
		urlbuf++;
	}

	*dst = '\0';
}
#endif

/****************************************************************************
 * Name: urlrawencode
 *
 * Description:
 *   There must be enoug space in urlbuf. In the worst case that is 3 times
 *   the length of str
 *
 ****************************************************************************/

#ifdef CONFIG_CODECS_AVR_URLCODE
void urlrawencode(char *str, char *urlbuf)
{
	char c;
	while ((c = *str)) {
		if (c == ' ' || isalnum(c) || c == '_' || c == '-' || c == '.' || c == '~') {
			if (c == ' ') {
				c = '+';
			}

			*urlbuf = c;
			str++;
			urlbuf++;
			continue;
		}

		*urlbuf = '%';
		urlbuf++;
		int2h(c, urlbuf);
		urlbuf++;
		urlbuf++;
		str++;
	}

	*urlbuf = '\0';
}
#endif
